The seaside resort of Qingdao in east China has been swamped with algae and, we have to say, it doesn't look very appealing!
The 'sea lettuce' appeared just last month but already more than 20,000 tonnes of it have been removed from the water.
It now covers the size of a football pitch across the surface of the sea but, although it is meant to be edible and extremely healthy, it's not very inviting.
However, while we would be put off, some brave bathers have still been spotted having a paddle!
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